docs: def labels(self, qids):
          """
          Returns Wikidata labels query string
          """
          if len(qids) > 50:
              raise ValueError("The limit is 50.")
  
          self.domain = 'www.wikidata.org'
          self.uri = self.wiki_uri(self.domain)
  
          query = self.WIKIDATA.substitute(
              WIKI=self.uri,
              ENDPOINT=self.endpoint,
              LANG=self.variant or self.lang,
              PROPS='labels')
  
          qids = '|'.join(qids)
          query += "&ids=%s" % qids
  
          self.set_status('labels', qids)
  
          return query